D
Film cameras and digital cameras work in a similar way.
Film cameras
After all, a film camera is basically a light – proof (不透光的) box. It has a lens (镜头) system to focus light onto the film at the back of the camera.
Let’s suppose that we are outside on a beautiful summer day trying to take a picture of the family dog. We are using a film camera. We finally get the dog to lie still. You point the camera at him. What happens? Light goes into the camera lens and hits the shutter. In other words, nothing happens yet. Now let’s say that the dog looks really cute and you decide to snap a picture. What happens? When you press the button, the shutter open for a very short period of time. A small amount of light passes through and hits the film at the back of the camera. This creates an upside-down and reversed (反向的)image on the film.
When you finish the roll of the film, you can take it to the photo shop to develop it and you will have a great picture of your dog!
Cameras come with different lens lengths. Why does it matter? Many small cameras have shorter focal lengths, which means that there is a small distance between the lens and the place where the light focuses at the back of the camera. This gives you a large view of the area you are taking a picture of. Lenses with a long focal length show a smaller area but allow you to focus on distant objects and make them bigger. They are often called telephoto lenses. A good example of a long focus lens is one that is used by sports photographers to get photos of football players as if they were standing right beside them.
Digital cameras
In digital cameras, the light falls not on film but onto a sensor (传感器)called a CCD (Charge Coupled Device). This digitally converts(转变) light and colour into a digital information or pixels (象素). The CCD is the heart of any digital camera and usually the most expensive part ---- depending on how good it is.
67．Which of the following statements is TRUE?
A．Both digital and film cameras focus light onto the film.
B．All cameras have a sensor.
C．Digital cameras and film cameras have something in common. .
D．Small cameras usually have longer focal lengths.
68．In the “Film cameras” part, you fail to take the picture of the dog because _____.
A．light goes into the camera lens and hits the shutter
B．you haven’t aimed the camera at the dog
C．the image of the dog is not created
D．the sensor fails to convert light and colour into a digital information
69．The main reason that sports photographers can get clear and big photos of players is that _ ___.
A．they use digital cameras B．the lens of their cameras is excellent
C．their focus lenses are short D．their focus lenses are long
70．Generally speaking, a digital camera’s price is ____.
A．closely related to the quality of the CCD
B．irrelevant to the quality of the CCD
C．closely related to the lens
D．irrelevant to the lens
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浙江新课程三维目标测评课时特训系列答案科目：高中英语 来源： 题型：阅读理解
How can you find out what is going on inside a person’s body without opening the patient’s body up? Regular X rays can show a lot. CAT scans can show even more. They can give a complete view of body organs.
What is a CAT scan? CAT stands for a kind of machine. It is a special X-ray machine that gets a 360-degree picture of a small area of a patient’s body.
Doctors use X rays to study and determine diseases and injuries within the body, X rays can find a foreign object inside the body or take pictures of some inside organs to be X-rayed.
A CAT scanner, however, uses a group of X rays to give a cross-sectional（横截面）view of a specific part of the body. A fine group of X rays is scanned across the body and around the patient from many different directions. A computer studies the information from each direction and produces a clear cross-sectional picture on a screen. This picture is then photographed for later use. Several cross sections, taken one after another, can give clear “photos” of the entire body or of any body organs. The latest CAT scanners can even give clear pictures of active, moving organs, just as a fast-action camera can “stop the action”, giving clear pictures of what appears unclear to the eye. And because of the 360-degree pictures, CAT scans show clear and complete views of organs in a manner that was once only shown during operation or examination of a dead patient.
Frequent appearance before X rays can cause skin burns, cancer or other damage to the body. Yet CAT scans actually don’t cause the patient to more radiation than regular X rays do. CAT scans can also be done without getting something harmful into the patient, so they are less risky than regular X rays.
CAT scans provide exact, detailed information. They can quickly find such a thing as bleeding inside the brain. They are helping to save lives.
What is NOT true of a CAT scan?
A．It is safer than regular X rays.
B．It makes use of computer techniques.
C．It can stop the action of an organ for a short time.
D．It gives clear pictures of active, moving body parts.
The underlined words “a foreign object”（Para 3）most probably refer to .
A．a badly injured part inside the body
B．a new thing that is unknown to the doctor
C．a strange organ that has grown in the body
D．an object that gets inside the body by chance
What is the special use of the latest CAT scanners?
A．It provides clear photos of moving organs.
B．It can take 3-dimension（三维）pictures of inside organs.
C．It won’t cause serious skin burns, cancer or other damage to the body.
D．It helps to find out what is going on inside a person’s body without opening it up.
We can infer from this passage that .
A．patients in front of CAT may suffer from a bit of radiation
B．doctors need no opening-up of the body with CAT scanners
C．CAT scanners are more expensive than regular X-ray machines
D．CAT scanners can take photos of either the whole body or a part of it
The best title of this passage might be .
A．the Newest Medical Invention
B．New X-ray Machine to Save Lives
C．How to Avoid the Damage of X Rays
D．Advantages and Disadvantages of CAT Scanners
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科目：高中英语 来源： 题型：阅读理解
Japanese people,who never miss a chance to be photographed,were lining up to get their pictures on a postage stamp．Vanity（虚荣）stamps with personal photographs went on sale for the first time in Japan as part of an international postage stamp exhibition．The customer’s photo was taken with a digital camera and then printed on stamp sheets,a process that takes about five minutes．Sold in a sheet of 10 stamps for $8．80,little more than the cost of lunch in Tokyo,each stamp printed a different scene from a traditional painting along with the photo．
The stamps can be used normally to mail a letter,and postal officials hope they will help encourage interest in letter writing in the Internet age．“Certainly e-mail is a useful method of communication,but letters are fun in a different way,”said Hatsumi Shimizu an official in the Post Ministry．“We want to show young people that letters can be fun too．”
While similar stamp sheets appeared in Australia in 1999 and are now sold in some nations and territories,Japan’s fondness for commemorative photos is likely to make them especially popular here．Indeed,officials had prepared 1 000 sheets but they were sold out in less than 30 minutes．Although the stamps are currently only available as a special service during the exhibition,postal officials said they may start selling them on a regular basis in the future．
The best title of this passage might be______．
A．Never Miss a Chance to be Photographed B．Your Own Face on a Postage Stamp
C．First Japanese Postage Stamps with a Photo D．Letters are as Fun as E-mails
By saying“little more than the cost of lunch in Tokyo”,the author really means______．
A．this service is not very expensive B.the cost of this service is very high
C．food in Tokyo is very dear D．$8．80 is a very small amount of money
The purpose of this activity is______．
A．to make the international postage stamp exhibition more interesting
B．to make more stamps for normal use C．to draw interest in writing letters
D．to satisfy Japan’s fondness of commemorative photos
Which of the following is true according to the passage?
A．Japanese people like to take photos． B．This kind of stamps must be used to mail letters．
C．Japanese people can get this kind of stamps easily after the stamp exhibition．
D．This service is more popular in Japan than in other places．
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科目：高中英语 来源：2014届四川省高二10月月考英语试卷（解析版） 题型：阅读理解
In the world today, there are millions of surveillance cameras, or “spy cams”, watching and monitoring our daily activities. There are some benefits of course, as people who are breaking laws can be watched and caught using cameras and this helps keep our society and public places safe. These cameras are everywhere and most are openly visible on roads, in airports, businesses, shopping centers and government buildings and even in lifts. Even schools have started using spy cams to watch student activity and behaviour.
The cameras are so common now that we hardly ever even notice them. But the problem lies with the ones that are hidden away from our eyes and are unseen. Technology has helped develop tiny cameras that can be very well hidden and they can “spy” on shoppers, workers, babysitters and people in hotels and clubs without the people even knowing.
It is these spy cams that people feel are an invasion of privacy. Recently, in the US, there have been a number of court cases against babysitters whose actions have been recorded by their employers on hidden cameras.
The number of cameras in public and private areas is on the increase and with rising crime rates and the recent terrorist attacks, more and more surveillance cameras are being used to watch us. This means that we all have to be aware that our employers, department stores, police and even some of our friends could be spying on us at any time!
1.In the writer’s opinion, surveillance cameras _______. .
A．do more good than wrong
B．are overused
C．should be very popular
D．ought to be more widely used
2.In what way can the surveillance camera benefit the public?
A．By helping keep social safety.
B．By monitoring the employees.
C．By watching the students in class.
D．By spying on customers.
3.According to Paragraphs 3 and 4, people _______ the use of hidden cameras.
A．object to
B．agree to
C．feel happy about
D．are fearful of
4.Spy cams will be more widely used in the future because _______. .
A．all people want to spy
B．of the invasion of privacy
C．people enjoy being watched
D．of terrorist attacks
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科目：高中英语 来源：2015届江西省高一第一次月考英语试卷（解析版） 题型：完型填空
It was a cold winter afternoon. Robert stopped for a moment as he crossed the bridge and looked down at the river below. There were hardly any 36 on the river. Near the bridge, however, almost direct below, 37 was a small canoe (独木舟), with a boy in it. The boy was wearing 38 and shivering (颤抖) with cold, Robert noticed. Just then he heard a cry, “Help! Help!” The cry 39 from the river. Robert looked down. The boy was 40 the water and his canoe was floating away. “Help! Help!” he called again.
Robert was a good 41 . Taking off his clothes, he 42 into the river. The 43 water made him tremble all over, 44 in a few seconds he reached the boy. “Don’t be afraid,” he said and started to swim towards the river bank, 45 the boy with him. But at that 46 he noticed a large motor boat under the bridge. There were several people on the boat, all 47 in his direction. Robert 48 to swim towards the boat.
“Give me a hand,” he shouted 49 he got near the boat. He 50 up into a row of faces. “It’s funny,” he thought. “They look so 51 .” Silently they helped the boy into the boat and 52 him in a blanket (毯子). But they did not move to 53 Robert.
“Aren’t you going to pull me 54 , too?”
“You!” said one of the men. Robert noticed that he was standing next to a large 55 . “You! Why, we were making a film and you spoiled (破坏) a whole afternoon’s work! You can stay in the water!”
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